Improvement in distilling hydrocarbon oils



: To all whom it may costiera:4

UNITED STATES PATENT OFFICE.

HERBERT w o. TWEDDLE, oF rrrrrsn'une, PENNSYLVANIA.

nMPR'ovEM-nr' *m oisTiLLmc-HvonocARsoN ons. 1

" specification forming psi: of Letters Patent no. n, les, cmd linwinnen1o, ist?.-

Be it known that I, HERBERT W. C. TWED- DLE, of the city of Pittsburg,in the county of Allegheny and State of Pennsylvania, have invented anew and useful Improvement in Distillation of Hydrocarbon Oils ,Hand Ido hereby declare the followingto be a full, clear, and exactdescription thereof, reference being had to the accompanying drawings,making a part of this specification, in which-f Figure 1 is partly asideand partly a sec- .tional elevation of the apparatus I employ in theVprocess of distillation; and Fig. 2 'is a rear end view of the same,partly in section. Like letters of reference indicate like parts ineach. f

The nature of my invention consists in distilling hydrocarbon oils, bycausing the oil' to iiowin a thin iilm or layer over the surfaces ofa-series of heated pipes in a. vacuum-still,

withor without the application of superheated steam; and in securingacontinuous and complete distillation of such oils, by causing them -toflow over the surfaces of a succession of such pipes in di'erent stills,the Atemperature of the pipes increasing in each successive still, so asto drive oli' first the more volatile ingredients, and then those lessso, and so on until only the residuum remains; also, in the applicationof such processpto the redistillag tion of lire-distilled, residual, andlubricating This processbfv distillation may be vcarried n on in varioustrays; but the devices which I "the u se of an air-pump, or in otherknown way, and connect them to the condensers B2 C by the goese-necks B1C1, respectively. In each of the stills B O is a series or coil of pipe,c, each pipe of the series or rcoil passing through the stillhorizontally, but one being arranged over another in any desirablenumlier of vertical rows, and all connected together by aconnection-pipe, d, or other equiv;h alentg device. Above each verticalrow of such pipes a is placed a trough, a', which has small perforationsin the sides Vor bottom, as seen in Fig. 1, and a serrated edge, c,underneath. Below the series or coil a is placed a series of perforatedpipes, e, for` admitting superheated steam, such pipes being joined`rated troughs a. Through the perforations in each trough a' the oil runsdown, gathers on the points of the serrated edges' o, whence it fallsonto .the steam-pipes a, dropping or running from pipe to pipe, andpassingin a thin ilm over the surfaces of such pipes. A

.current of dry or superheated steam passingA in at the valves :v wkeeps such p ipes a heated to a high temperature; consequently the dropsor streams of oil coming in contact with and passing over them aresubjected to the action of a heated surface relatively large, whichcauses it to volatilize 'with great rapidity, the more so as thepressure of the atmosphere is already removed from the inside of thestill by the air-pump, as hereinbefore stated. Fluids in motion, also,it is well known, vaporize more rapidly than fluids atl rest so that bycausing the oil toi'iiow over heate surfaces in a vacuumI secure anexceedingly rapid evaporation. I also facilitate this process bybringing jets of snperheated steam from the pipes e in contact with theoil while iiowi n g over the surfaces of the pipes a. A serrated edgemay be placed under each such pipe a to secure a more even distributionof the oil in its liow from pipeto pipe. Steam is admitted to the pipese through .the valves w1 m1, Vand the water of4 condensation drawn` oii'from th pipes a and e by the cocks :v3 A y By the use of these devicesthel lighter or more volatile oils are driven olf in the iirst still'B'in theform of vapor, which, being cary ried over by the goose-neck Bl tothe condenser B2, is there condensed,`as presently to be described. u u

Such of the heavier oils as are .not thus vaporized in the lirst still,B, fall to the bottom. of the still, whence, by a pipe, j', they areconductedintothenextstill,C. Theretheyarcdischarged into perforated andserrated troughs a', ow onto and over pipes` a, and other V01-, atileingredients ,are driven oi' in vaporous form by an increased degree ofheat received therefrom and from the superheated steafln, which escapesVYfrom the jet-holes inthe pipes e, in the manner already dcscri bed.The residuum, with the oils not yetvolatilized, it' any,

falls to the bottom 'of the still C, whence it is conducted to anotherstill and similarly treated, A or,lby a pipe, j, is discharged into areceiver,

D, in which a vacuum is also preserved. From this it isdrawn off by acock,-g,'at pleasure.

A pipe, h, connects the receiver D with the still C for convenience in`securing a vacuum v inthe former, and for-thc purpose of conduct! ingover any vapors which may arise from the residual matter in snchreceiver.

The steam used in this process may be admitted into the pipes a and e ofeach still scparately 'or it may be first admitted into the pipes a ande of the last and lowest of such stills, and conducted thence by pipes iTinto the pipes a e of the next still, and so on till the last orhighest still is reached. In Ithis way I apply the steam when hottest tovolatilizing the heavier oils, which, of course, require for thatpurpose the greater degree of4 heat; and, as the temperature ofthe steamis reduced 'mits passage from still to still, I ap ply it ataQ-lowertemperature to driving oif the lighter oils in each higher still; or, in

other. words, I'secure a continuous and complete distillation ofhydrocarbonoils by'vaporizing the lighter ingredients with acomparatively low degree of heat, the next heavier in gredieuts by ahigher degree of nheat, passing the residual oil for that purpose fromstill to still, so as to subject it to a constantly-increas ingtemperature in the successive stills till. only the residuum remains.Superheated steam` may, if preferred or found necessary,

' used in the pipes was well as in the-pipes e.

By the use of this process I render unnecessary the application of tiremilite-heat directly to the oilD at. any stage of the distillation,whereby Iavoid all possibility of a fire or an explosion, which are thechief sources of danger in the distillation of hydrocarbon oils.

`2 .y v 19,126 v jets of `cold water into Vthe condensing-chamber Gz tocondense the oily vapors. Cold water` is passed through the pipes -n forthe 'same purpose. Water is admitted and drawn oi by the cockss s. Thecondensed oil is drawn oft' at the cock s with the condensed` water, ifl there be any, and discharged into` atank or -other receptacle throughan air-pump or otherwise. Thecondensers may be so constructed that thepipes n shall run horizontallythrough th'e condensing-chamber, if sopreferred.

It is not absolutely ynecessary that onestill should be higher thananother, since, by creating; a more complete-vacuum .in the second stillthan in the first, and so on in 'each successive still, the residual orunvaporized oil `in the bottom of each still may 'be'forced into thenext at the same or a higher level.

The advantages ofthis process of distillation are, among others, irst,dispensing entirelywith theapplicatio to the oil of fire or a fire-heat,as already stated; second, a more rapid vaporization of the oil;third,collecting the vapors of thellighter and heavier oils andcondensing them in separate receivers, whereby-a quality of oil can beproduced for illuminating purposes perfectly freel from the volatileingredients which render them dangerous v .odor and a bad color, toremove which the oil is generally treated with acids, alkalies, &c.

My process of distillation obviates the necessity of refining the oil,with a consequent saving of time, trouble, and expense, and alsoproduces an article superior in quality to the common lire-distilledrefined oils. I also apply my improved process to the distillation ofthe residual aud lubricatingk oils produced by tire-distillation, withthe same benefits as are `above set forth.

In carrying on the process of distillation above set forth, I do notlimit myself to the particular devices described; but 1 What I claim asmy invention, and desire to secure by Letters Patent, is-

1. In distilling hydrocarbon oils, vaporizing the oil by causing it toflow -in a thin tilm or layer over the surfaces of a series of heatedpipes in a vacuum-still, with `or without the application of superheatedsteam, substantially as abovev described.

2.v The application of the process of distillation herenbefore describedto the redistillation of re-distilled oils, for the purpose tofproducing an oil similar to the rened oil of commerce, substantially asabfle set forth.

n.126 I s 3. Securing a' continuous and complete dis- I In testimonywhereof I, the said HERBERT tillation of hydrocarbon oils by causingtheV W. C. TWEDDLE, have hereunto set my hand. oil to ow over thesurfaces of a succession of heated pipes in di'ereut vacuum-stills, theHERBERT W. O. TWEDDLE.

temperature of such pipes increasing in each l i" successive still, soas to drive o' at first the Witnesses: l

more volatile ingredients and then those less A. S. NICHOLSON so, and soou till only the residuum remains, G..H. CHRISTY.

substantially as hereinbefore described.

